Two scientists, Elsa and Clive (Sarah Polley and Adrian Brody) are breeding slimy, oozy, genetically engineered sluglets about the size of cats so that a new protein can be harvested and synthesised by the big drug company funding them. Frontier stuff, and -- almost -- possible. The first wave of genetic modification produced sensible guidelines, but the moral issues evidently are a big concern for Canadian writer-director Vincenzo Natali (Cube), because our heroes, Clive and Elsa, never stop talking about them. When the drug company closes down their laboratory, Elsa's the one who pushes their work that little bit further, adding a bit of human DNA to the mix.

In the old days of sci-fi melodramas, the mad scientists came with white hair and Einstein moustaches. You knew. This pair are tricky -- they are so cutting-edge you can visualise the colour magazine spreads -- so it takes time to realise we are dealing with one very nutty scientist indeed, and a complicit partner.

And their little offspring? Is it a plane? Is it a bird? A fish? A fowl? Whatever it is, it's smart, it's female, and Elsa starts to become very maternal as she raises it, with increasing difficulty.

What's the filmmaker up to? Maybe we should be warned when one of them dashes from the laboratory exclaiming, po-faced: 'It's alive! It's alive!'

The hybrid offspring, Dren (Delphine Cheneac), is beautiful, like one of those fleshy, mutant scuptures by Patricia Piccinini. As she grows, the film changes tone. By the final act, it too has mutated into fully fledged kinetic horror.

Like the mutant progeny, Splice is an unsucessful hybrid: half moral fable, half mad scientist makes monster flick. Worth a look, but no prizes for guessing the ending.